Climatic effects on the reproductive biology of Caiman latirostris (Crocodylia: Alligatoridae)

Abstract

Reproductive aspects, like number of nests produced per season or clutch size (number of eggs per nest), of broad-snouted caiman (Caiman latirostris) may be affected by a climatic variables such as rainfall and temperature. The success of caiman reproduction is not only affected by the amount of rainfall, but also by the time elapsed during which it takes place. In this study, we present evidence of a positive relationship between the number of nests produced and the amount of precipitation on the water heads (“Bajos Submeridionales”) during March. Surprisingly, there was not a significant relationship when considering local rainfall and temperature. During one event of El Niño phenomena the number of caiman nests was the highest in eight years of monitoring, besides a remarkable low number of nests were produced during La Niña. There was not a significant relationship between clutch size and rainfall or temperature. This information is useful for the ranching programs, because managers will be able to estimate, nine months in advance, the number of nests for harvesting. Another positive aspect is that this information can be used to establish nests' searching strategies, and number of eggs to incubate and hatchlings to raise. Thus, this will help planning management strategies in support of conservation efforts for the species during extreme climatic events.

Influence of Climatic Variables on Corporal Attributes of Adult Female Caiman and Their Relationship with Reproductive Success

“…Once the winter ends and spring begins in September, when the temperature begins rising, the caimans return to their feeding activities, preparing for the new reproductive season. Previous research on Caiman latirostris found a positive relationship between the number of nests produced in the wild and rainfall in March in the headwaters of the rivers tributary to the localities evaluated in Santa Fe province (Simoncini et al, 2011).…”

“…In Caiman latirostris (Daudin, 1802) there is evidence associating reproductive performance with climatic conditions. Previous work on this species found a positive relationship between the number of nests produced in nature and rainfall (Simoncini et al, 2011). Although several aspects of the reproductive ecology of this species have been studied (Larriera et al, 2004;Simoncini et al, 2011;Piña et al, 2015;Portelinha et al, 2015), it is not yet known how attributes such as body size, body condition, and physiological condition of reproductive females may influence reproductive patterns.…”

“…Previous work on this species found a positive relationship between the number of nests produced in nature and rainfall (Simoncini et al, 2011). Although several aspects of the reproductive ecology of this species have been studied (Larriera et al, 2004;Simoncini et al, 2011;Piña et al, 2015;Portelinha et al, 2015), it is not yet known how attributes such as body size, body condition, and physiological condition of reproductive females may influence reproductive patterns. In this context, assessing how variables such as rainfall and temperature affect the reproductive performance of caimans is important, as oscillations of these variables produce extreme conditions in water availability (by floods or droughts; Heinzenknecht, 2005;Peñalba and Vera, 2005).…”

A Importância Das Técnicas De Manejo Cat Friendly E Como Praticá-Las

“…O nome Caiman latirostris (Figura 1), tem como significado rostro largo, característica peculiar e diferente dos demais crocodilianos: a largura do seu focinho (PIÑA, 2007;LARRIERA, 2011;COUTINHO et al, 2013). O jacaré-de-papo-amarelo é representante da Subclasse Archosauria, Ordem Crocodylia, Família Crocodylidae, Subfamília Alligatoridae (RUEDA-ALNIBACID et al, 2007;LUZ, 2012).…”

Eggshell structure in Caiman latirostris eggs improves embryo survival during nest inundation

“…After 70 days of incubation (depending on temperature [23]), hatching occurs from the end of February into mid-April [24]. Egg incubation occurs during the warm and rainy months [25,26], increasing the probabilities of embryonic death due to inundation. Female broad-snouted caiman use floating vegetation for nesting when available (they utilize the vegetation available to make the mount nest), because depredation in floating vegetation is lower [13,15], and also inundation is minimized if the nest floats on the water surface.…”